Fluids in reservoirs of motor vehicles propagate a nose when they hit a wall of reservoir or splash inside a reservoir. For example, during vehicle acceleration or deceleration an occupant of the vehicle may hear the noise of fuel moving inside a fuel tank. This problem is more apparent with hybrid vehicles that have less interior noise with an electric motor operating than when the combustion engine is operating.
A known solution to reducing the noise propagating from a fluid reservoir is to use a baffle that restricts and directs the motion of the fluid inside. Another solution is to use an open cell foam material or mesh material inside a tank that restricts and directs the motion of the fluid inside. There is a problem to inserting a noise reducing component inside a reservoir. There is a need for a means that is not cost prohibitive and does not negatively impact on productivity. There is a need for a means of inserting a noise reducing component without adversely affecting the permeability of the reservoir.
The blow molding process is a common technique to make hollow articles such as fuel tanks or portable transport containers. The disadvantage of this polymer processing method is that the integration of components inside the hollow plastic article after molding is very difficult and limited. For example, fuel tank components can be added after molding by inserting them through cut holes. These holes are subsequently covered by caps or with fuel tank components leaving an additional permeation path for fuel vapour permeation from the inside to the outside.
Another process known in the art is a twin-sheet forming process. Two half-shells are formed from sheets and welded together in a second step. It is possible to insert components between two half-shells before they are welded. A disadvantage of this thermoforming process over flow molding is that the thickness of the extruded sheet is uniform resulting in uneven thinning in the finished part in high blow ratio areas. Another disadvantage is that there is an additional time and energy required to heat up the two-shells in order to weld the shells.
Another process for producing hollow plastic articles is a twin-sheet blow molding process. The process encompasses forming a hollow parison with a blow molding extrusion apparatus, splitting the parison into two sheets, thermoforming the sheets to form half-shells before the welding process. The disadvantage of this process is that a capital investment is required for parison splitting and twin sheet handling devices with poorer productivity arising from operating, maintaining and cleaning the additional devices.
There is a need for a fluid reservoir with a noise reduction baffle and a method of manufacturing that overcome the aforementioned problems.